Question

An object with a mass of `7 kg` is on a surface with a kinetic friction coefficient of `8`. How much force is necessary to accelerate the object horizontally at `31 m/s^2`?

Answer 1

I found `765.8N` (but check my maths!). Ciao.

Explanation:

Have a look:

So we get that:
`N=W=mg=7*9.8=68.6N`
From the first equation (alomg `x`) we get:
`F-mu_kN=ma`
`F=(8*68.6)+(7*31)=765.8N`